TOXINS OF THE HIGHER PLANTS AND ANIMALS 119 



The Toxin of Hay-fever. Pollen toxin has been described by 

 Dunbar 1 as the etiologic factor in the production of hay-fever. In all, 

 the pollen of 25 varieties of grass and seven varieties of plants have been 

 found capable of producing attacks of hay-fever in susceptible persons. 

 This susceptibility to pollen intoxication is, fortunately, limited, and the 

 sudden onset of an attack and the characteristic symptoms indicate an 

 anaphylactic reaction due to sensitization with pollen protein. Dunbar 

 has succeeded in producing a pollen antitoxin, which will be described 

 in the chapter on Passive Immunization; the reports of various 

 observers are, however, at variance in regard to its therapeutic value. 



ZOOTOXINS 



The most important animal toxins (zootoxins) are those of the toad, 

 spider, snake, scorpion, and bee. The most striking characteristic of 

 these toxins is that an immunity against them can be established; in 

 this respect they resemble true toxins. All are quite complex in struc- 

 ture and properties, and all are more or less hemotoxic. 



Snake Venoms. 2 Medically, these are of particular interest. They 

 were first thoroughly investigated by S. Weir Mitchell (1860) and 

 Mitchell and Reichert (1883), and have aroused considerable attention 

 because of their similarity to bacterial toxins and the aid their study 

 has been in the elucidation of immunologic problems. 



Properties of Venom. In 1883 Mitchell and Reichert described two 

 poisonous proteins, constituents of venom, one of which seemed to be a 

 globulin and the other a proteose or "peptone." Faust 3 believes that 

 the poisons are not proteins, but glucosids free from nitrogen, and that 

 they belong to the saponin group of hemotoxic agents. It may be that 

 these glucosids are bound to proteins, and can be removed with the 

 globulin in fractional separation, or that they may come down, at least 

 in part, with the albumoses of the venom. 



Various enzymes have been found in venoms; e.g., proteases (Flex- 

 ner and Noguchi) and lipases (Noguchi); the latter probably have a 

 definite relation to many of the effects of venom intoxication, especially 

 hemolysis and fatty degeneration of the tissues. 



The poisons, as a rule, produce both local and severe general dis- 

 turbances, the rapidity of the onset of the symptoms and the prognosis 



x For full review of this subject see Glegg: Jour. Hygiene, 1904, 4; Liefman: 

 Zeit. f. Hygiene, 1904, 47, 153; Wolff-Eisner, Deut. med. Woch., 1906, 32, 138. 



2 See Faust: "Die tierischen Gifte," Braunschweig, 1906; Noguchi: Carnegie 

 Institution Publications, 1909, No. Ill; Calmette: "Les venins," etc., Paris, 

 Masson, 1907. 



3 Arch. exp. Path. u. Pharm., 1907, 56, 236; 1911, 64, 244. 



